Ductor device for inking mechanisms for printing presses



Dec. 24, 1957 R. P. WILLARD 2,817,293

DUCTOR DEVICE FOR mxmc MECHANISMS FOR PRINTING PRESSES Filed April 6, 1955 FIG. 2.

INVENTOR ROBERT E WILLARD ATTORNEYS United States Patent flice 2,817,293 Patented Dec. 24, 1957 DUCTOR DEVICE FOR INKING MECHANISMS FOR PRINTING PRESSES Robert P. Willard, Durham, N. H., assignor to Kidder Press Company, Inc, Dover, N. H., a corporation of Delaware Application. April 6, 1955, Serial No. 499,557

4 Claims. (Cl. 101350) tain roll to the transfer roll or ink drum which forms the initial unit of the bank of inking rolls, by means of a ductor roll. These ductor rolls, some of which are of considerable mass, especially in the wider printing presses now in use, have been mounted for rotation in brackets which are pivotally carried by a portion of the press frame, and the ductor rolls have been connected by suit able means with the press drive to oscillate them between the fountain roll and the ink drum.

Now, the fountain roll must of necessity rotate rather slowly, while the ink drum and the other rolls of the inking installation have a very high surface velocity corresponding'to the rate of rotation of the printing rolls or the oscillation of the printing plate, whether the press is of the rotary or bed and cylinder type.

As an example of the great disparity between the velocities of the fountain roll and the ink drum, it may be stated that in certain presses the surface velocity of the ink drum is approximately 800 feet per minute. Thus it will be seen that the ductor roll during its. oscillation between the ink fountain roll and the ink drum must alternately have to be rotating at about 800 feet per minute as it rolls on the surface of the ink drum and to be barely moving as it rides on the surface of the ink fountain roll. which is ordinarily only intermittently driven by a ratchet feed.

As printing press speeds have increased during the years, the vibration and pounding, and consequent wear and tear on the ductor roll have increased very rapidly, with the necessity of continuous alternate acceleration from substantially zero speed to the neighborhood of 800 feet per minute, and the deceleration from this ink roll speed back to practically zero, as the ductor roll contacts the ink fountain roll.

As printing presses have become wider the ductor rolls have had to be made of larger diameters and of heavier construction to correspond with the increase in width. This of course means that the inertia of the parts is greater and the entire printing and inking system is subjected to very severe usage when the relatively heavy ductor rolls have to be brought up against the surface of an ink drum. revolving at the suggested speed of 800 feet per minute, and accelerated to that speed in a fraction of a second.

It is therefore the principal object of the present invention to provide a novel and improved transferring means for carrying the ink from the fountain roll to the inking rolls which will obviate the objections and difliculties attendant upon the use of heavy ductor. rolls. In substitution for the conventional ductor roll the present invention contemplates the provision of a mechanism of low mass which can be reciprocated at a high rate of speed between the ink drums and the fountain roll and which does not have a rotary motion of its own.

The invention in its preferred embodiment contemplates the provision of a ductor blade which is mounted in the press frame for swinging movement in the vicinity of the frame roll and ink drum whereby one edge of the blade comes in contact with the fountain roll in order to scrape an increment of ink from the roll and then swing toward the ink drum so as to deposit the gob of ink collected from the fountain roll upon the ink drum. Then the blade swings back toward the fountain roll and collects another gob or increment of ink.

It is a further object of the invention to provide in conjunction with this novel means for transferring the ink, additional means for collecting any spillage or splash of ink which may occur due to the high rate of rotation of the ink drum, and the impingement of the gob of ink upon the drum as delivered by the ductor blade. This means may conveniently take the form of a. roller running in contact with the ink drum or transfer roll and disposed beneath the point of contact of the ductor blade with the drum and serving to catch any spillage of ink and work it onto the surface of the ink drum.

One of the advantages of the present invention resides in the fact that the ductor blade, being a relatively simple, light, and easily accessible element, is very readily washable. Thus it is far superior to the conventional ductor roll and also to other expedients which have been experimented with in this connection, since these prior devices are so complex in construction and installation that they cannot be easily and practically washed up when changing from one color of ink to another.

Another advantage of the present invention stems from the regularity and constancy with which the ductor blade transfers the gob of ink from the fountain roll to the ink drum. This uniformity of operation is a decided advantage in metering the supply of ink to thepress according to the predetermined adjustment of the fountain system.

Other objects and features of novelty will be apparent from the following specification when read. in connection with the accompanying drawings in which one embodiment of the invention is illustrated byway' of example.

In the drawings:

Figure 1 is a schematic, vertical, sectionalview of the: invention as applied to the inking of a high: speed rotary press;

Figure 2 is similar to Figure 1, showing the first step of removing the ink from. the fountain roll;

Figure 3. is. similar to Figure 2, showing the application of the ink to the first transfer roll; and

Figure 4 is similar to Figure 3, showing the action of the gob-roll.

The invention may be incorporated in any type of rotary press having a fountain roll and a transfer roll or ink drum, but is particularly suitable for use in a continuous high speed .color press. The press illustrated in the drawings is of conventional construction. with respect to the mounting and driving of the printing cylinders and sheet feeding mechanism. The ink feeding mechanism comprises a fountain 10-, wherein the ink 11 is retained behind the fountain roll. 12 which roll is rotated slowly either intermittently or continuously and. carries a film of ink'on its surface during operation. of. the press. A thin ductor blade 13, pivoted on. an. oscillating shaft 14 and offset therefrom by means. of the arms 15, accumulates the ink on its lower edge in. the form of a gob or increment 16, from the surface of the slowly rotating fountain roll 12, as shown in Figure. 2.. This ductor blade then oscillates from the position shown in Figure 2, tothe position shown in Figure 3,. and;

applies the gob of ink 16 to the surface of the rapidly rotating transfer roll or ink drum 18. The ink applied to the surface of this roll comes in contact with the dis tributing rolls 20 which carry the ink to the distributing drum 21, the ink being then applied to the plate cylinder 23 by means of the distributing rolls 22.

Due to the fact that the ink drum 18 is travelling at a high rate of speed some or all of the increment of ink 16 may be thrown from the surface thereof by centrifugal force before it is smoothed out by contact with the distributing rolls 20 and evenly applied on its surface. A separate roll 19, preferably made of rubber, is so placed below and in contact with the ink drum 18 that such ink is caught on its outer surface, as shown in Figure 4. Such ink is immediately returned to the transfer roll 18 by the rotation of the gob catching roll. The ductor blade itself does not rotate and is of small mass and simply oscillates periodically to contact the fountain roll, pick up the increment of ink and carry it to the transfer roll. Its time of contact with the fountain roll may be mechanically controlled to regulate the amount of ink picked up and delivered.

This method of transferring the ink from the fountain roll to the first ink roll or drum avoids many difiiculties heretofore experienced because the ductor blade is stationary when in contact with the ink carrying rolls and does not require rotary motion as do the ductor rolls usually used; and it does not have to be accelerated and decelerated between contacts with the fountain roll and the transfer roll. The ductor blade is of low mass and is merely oscillated so as to first contact the fountain roll for a measured time interval, then the distributor roll, and the cycle is repeated. In the broader aspects of the invention, any method may be used for catching and conveying the spattered ink back on to the distributor roll, the rubber gob roll being one novel means for accomplishing this result.

In a typical rotary press the ink drum transfer roll 18 has a surface speed of approximately 800 feet per minute. It is made of steel and carries the ink across its surface so as to feed a film of ink on each of the distributing rolls contacting this ink drum which rotate at the same surface speed. This ink is then carried on to the surface of the successive rolls at a constant speed and is not subjected to great variations in surface speeds after leaving the ink drum as has been the case in the past. The spatter at the ductor blade is readily caught and returned to the transfer cylinder, and the ductor blade is much easier to clean than-the old ductor rolls. These advantages are of great importance in saving ink and in saving time when it is desired tochange the color of the ink being fed on to the press.

The present invention also has an outstanding advantage in that the ink picked up by the ductor blade is transferred to the transfer roll in an amount that may be very accurately controlled by regulating the time of contact with the fountain roll and rate of oscillation of the ductor blade, as well as the adjustment of the fountain, which control is simple and does not require the complicated mechanical devices necessary to such control as the heretofore used ductor roll, which not only had to be rotated at varying rates of speed but also oscillated and synchronized for contact with rolls with vastly different surface velocity.

It is evident that various changesmay be made in the arrangement of the component parts without departing from the spirit of the invention which is only limited by the claims appended hereto.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. An inking mechanism for high speed printing presses and the like comprising, in combination, a supporting frame, an ink fountain mounted on said frame and including a fountain roll, means for rotating said fountain roll at the conventional very slow rate, a train of ink transferring and distributing rolls mounted on said frame and including as its initial ink receiving element an ink drum, said fountain roll and ink drum having parallel axes and being disposed in spaced apart relationship, means for driving said train of rolls at high peripheral speeds, an oscillating ductor blade, a pivotal support on said frame positioned at a higher point than at least one of said parallel axes, said blade connected with said support and extending therefrom toward said fountain roll and drum, an operating edge on said blade parallel with the pivotal axis of said support, said blade disposed for swinging movement between said fountain roll and said ink drum to and from tangential contact at said operating edge respectively with said fountain roll and drum, the fountain roll at its point of tangency rotating in a direction toward the pivotal point of said blade and the ink drum rotating at its point of tangency away from said pivotal point, and means for swinging said blade, whereby said blade pares off a quantity of ink from the fountain roll during its proximity thereto, swings it toward said ink drum, and deposits said quantity of ink upon the rapidly rotating ink drum.

2. The inking mechanism set forth in claim 1 in which there is provided a supplemental ink collecting roll disposed in rolling contact with said ink drum adjacent the point of tangency of said blade therewith, to retrieve any portion of said quantity of ink which might be spilled upon application of the ink to the rapidly rotating drum by the ductor blade, and for re-applying said portion to the drum.

3. The inking mechanism set forth in claim 1 in which there is provided a supplemental ink collecting roll which is not a part of said train, said supplemental roll disposed in rolling contact with said ink drum beneath the point of delivery to the ink by the ductor blade, to retrieve any portion of said quantity of ink which might be spilled upon application of the ink to the rapidly rotating drum by the ductor blade and for re-applying said portion to said drum.

4. An inking mechanism for high speed printing presses and the like comprising, in combination, a supporting frame, an ink fountain mounted on said frame and including a fountain roll, means for rotating said fountain roll at the conventional very slow rate, a train of ink transferring and distributing rolls mounted on said frame and including as its initial ink receiving element an ink drum, said fountain roll and ink drum being parallel and disposed in laterally spaced apart relationship. means for driving said train of rolls at high peripheral speeds, an oscillating ductor blade, a pivotal support on said frame positioned between and above the axes of said fountain roll and said drum, said blade suspended from said pivotal support by its upper edge so as to swing through a limited arc to and from positions where it is in tangential contact respectively with said fountain roll and said ink drum, both of the lines of tangential contact being between planes passing respectively through the axis of said fountain roll and of said pivotal connection and the axis of said drum and said pivotal connection, and means for swinging said blade, whereby said blade pares off a quantity of ink from the fountain roll during its proximity thereto, swings it toward said ink drum, and deposits said quantity of ink upon the rapidly rotating ink drum.

References Cited in the file of this patent UNITED STATES PATENTS 1,185,669 Hoe June 6, 1916 1,185,670 Hoe June 6, 1916 1,514,991 Rees Nov. 11, 1924 1,593,991 Sharp July 27, 1926 

